Continuation Part 11: Amanda Knox/Raffaele Sollecito

[carbonjam72]

Turnip juice or blood. You decide.

Look, I can keep tweaking the thought experiment further if you want. You are already moving into the realm of fanciful explanation which lies beyond the zone of reasonable doubt and becomes too much to swallow. I mean, when was the last time you rolled in dirt and then came home and rolled around on the floor? Not impossible, just fanciful. And yes, I was posting in the context of a murder enquiry so it went without saying, I thought, that there had been a murder.

We agree the luminol evidence in this case is garbage. It doesn't even have zero value since the negative effect of the associated lies, certainly using Nencini's test (the one he sarcastically employed when rejected the defence request for re-testing of the clasp) obliges us to discount or discard all of Stefanoni's evidence. We don't agree whether luminol-only evidence can ever have probative value, even weak, non-zero value in the right context.

Is there ever a justification for not completing the confirmative testing on a luminol hit?

I guess we can disagree, I would though liked to have a better understanding. You have valiantly slogged through this question, so don't feel obligated.

 

[anglolawyer]

Is there ever a justification for not completing the confirmative testing on a luminol hit?

I guess we can disagree, I would though liked to have a better understanding. You have valiantly slogged through this question, so don't feel obligated.

I haven't really been talking about luminol. I am taking aim at the supposed test that each scrap of evidence must pass through before it can be combined with other evidence to form part of the global evaluation.

I speak and write reasonably good English without having much acquaintance with the finer points of grammar. The law is the same. I don't have a bunch of governing principles to consult when I embark on evidence gathering (which is a large part of what I do for a living) and I view with deep suspicion the Italian claim to have formulated a coherent set of them. In the course of the discussion I have refined the Italian rule to my own satisfaction as follows: relevant evidence, even prima facie weak evidence, gets in unless it's total crap.

Using this rule, the luminol evidence in our case does not make it for all the reasons discussed here which, by an amazing coincidence (not), Nencini refrains from mentioning at all. In my system (and yours probably) he would not be allowed to find the luminol revealed blood because such a finding flies in the face of a concession Stefanoni made that if TMB is negative you can be sure it's not blood.

However, formulating a universal rule that luminol-only evidence should never be used regardless of context, is a bit like saying ID evidence should never be used merely because it is known to be often unreliable. That rule is too wide.

 

[Kauffer]

Evidence

.... In my system (and yours probably) he would not be allowed to find the luminol revealed blood because such a finding flies in the face of a concession Stefanoni made that if TMB is negative you can be sure it's not blood.

This is right on the money! The Prosecution's own witness has diminished the value of the luminol 'evidence' to nothing. But this was part of the shameful deception. Mignini and Commodi take this to court knowing the evidence is bunk. The confirmation that the evidence is bunk -the TMB test- is deliberately withheld from the defence by Stefanoni. Once the deception had been uncovered, there should have been a mistrial and the defendants released. Charges should have followed for the gruesome threesome.

 

[Dan O.]

it's the other way round, Dan. The tiny and insecure mind is fit for operations that may resolve questions to the certainty needed to fly an object to Mars and land it there. A computer can do that. It takes broad experience of human affairs, wisdom, skill and true intellect to reconstruct the past via the trial process in face of the infinity of possibilities life throws up

The mind is a confirmation bias engine. It tries to explain everything in terms of the familiar and is therefore subject to latching onto an incorrect conclusion and not letting go. Science through a formal process tries to eliminate the bias.

 

[anglolawyer]

The mind is a confirmation bias engine. It tries to explain everything in terms of the familiar and is therefore subject to latching onto an incorrect conclusion and not letting go. Science Law through a formal process tries to eliminate the bias.

FTFY

 

[Dan O.]

Look, I can keep tweaking the thought experiment further if you want. You are already moving into the realm of fanciful explanation which lies beyond the zone of reasonable doubt and becomes too much to swallow. I mean, when was the last time you rolled in dirt and then came home and rolled around on the floor? Not impossible, just fanciful. And yes, I was posting in the context of a murder enquiry so it went without saying, I thought, that there had been a murder.

But you have already taken this to a fancyful direction because blood that escapes the body which it has to do in order to leave a tract for Luminol to spot typically doesn't retain the shape of the body. It sounds like a setup that somebody is trying to make look like a crime scene.

This reminds me of a scheme I hatched but never carried out: I lived in a rural area with lots of open fields near by. The local sherif had a helicopter with a big spotlight that he liked to fly around with at night. My thought was that if i took some beige colored glass beads and sprinkled them lightly on the ground in the shapes of bodies, from a distant helicopter illuminating the scene with a spotlight it would look like a field of naked bodies. But from up close and in the daylight it would look like nothing but a field of dirt. The only think stopping me is that I ddin't have an untraceable source for the beads. I hadn't thought then about making my own beads by tumbling broken beer bottles and the sherif has since crashed his helicopter.

 

[Dan O.]

I thought blood stopped pumping once heart stops beating. Blood will only seep, flow gently in this case. How does this fact explain the marks left on the duvet? Knowing duvets...and observing the type covering Meredith's body, it was of the uneven lumpy type yet blood had collected in a large pattern on it. Considering Meredith was on her back, and if her heart had ceased beating, one would expect any gentle blood flow to seep down her neck onto floor rather than arrive on the duvet placed over her I would have thought?

Perhaps it was absorbed through osmosis.

I believe that the duvet was already on the floor prior to the murder. Meredith's purse and the notebook on the bed are indications that the bed was clear when those items were deposited there either when Meredith came home or even prior to that. Being on the floor, it is possible for the duvet to come into contact with the pooling blood before it is flipped over the top of Meredith.

One of the things I would expect to see in the court evidence where the blood patern on the duvet is being presented as evidence is a photo of the duvet spread out showing those blood patterns on front and back. Without such photos it is rather difficult to discuss what the blood patterns on the duvet do or do not show.

 

[anglolawyer]

But you have already taken this to a fancyful direction because blood that escapes the body which it has to do in order to leave a tract for Luminol to spot typically doesn't retain the shape of the body. It sounds like a setup that somebody is trying to make look like a crime scene.

Au contraire! I am actually using LJ's recent blob on the carpet picture. I said nothing about the shape of a body, just the size, I think. But even I did, so what, the point remains the same: you can exclude all other likely sources of the reaction using TMB plus confirmatory testing or by other available circumstantial evidence such as I have described.

This reminds me of a scheme I hatched but never carried out: I lived in a rural area with lots of open fields near by. The local sherif had a helicopter with a big spotlight that he liked to fly around with at night. My thought was that if i took some beige colored glass beads and sprinkled them lightly on the ground in the shapes of bodies, from a distant helicopter illuminating the scene with a spotlight it would look like a field of naked bodies. But from up close and in the daylight it would look like nothing but a field of dirt. The only think stopping me is that I ddin't have an untraceable source for the beads. I hadn't thought then about making my own beads by tumbling broken beer bottles and the sherif has since crashed his helicopter.

Dan, you are one strange sumbitch.

 

[Chris_Halkides]

The DNA on the knife and the retest

Bill, when arguments are imported to this forum, progress can be made, because this is the default forum. Leila's last contribution on IIP on the subject was this: on February 4 2014:

Leila Shneps says:

Indeed, I wished for nothing so much as to discuss all the DNA evidence in more detail and above all the new test on the knife, but all the most interesting parts as far as I am concerned had to go due to the stringent word limit. Don't worry, further articles are in the making.

I thoroughly disagree that the new test on the knife, which for my part I would always have strongly recommended, is exculpatory. To me it proves exactly one thing: perfectly valid tests with clear results can be performed on extremely small samples, indeed on a sample so small that Vecchiotti wrongly claimed it was too small to test. If the result of 36I is accepted, then I can see no reason to exclude the one on 36B; certainly not the smallness of the sample. SNIP

Sampson,

Thank you for posting that quotation. There are some problems in the reasoning employed, and it might be worth one’s while to examine them.

First is the question of what is meant by reliability or unreliability of a DNA profile in the context of forensics. It has been known for more than twenty years that one can use the polymerase chain reaction (PCR) to obtain DNA profiles from as little as one or two cells (I posted this information many continuation threads ago). Therefore, it is no surprise whatsoever that the Carabinieri were able to obtain a profile.

Second is the question of how the test was performed and reported. From what I recall, the Carabinieri created a consensus profile from two amplifications, whereas Stefanoni did just one. Someone else may know better than I do, but didn’t they also deposit electronic data files? In addition Stefanoni’s lab was not even certified for standard profiling at the time. I am not sure about the forensic lab of the Carabinieri, but for argument’s sake, let us say it was. A third problem is that low template work should be done in dedicated facilities, not in the same lab as the regular testing. These problems are all swept under the rug when one makes a hasty comparison between the results from two different labs.

IMO the most important question is whether or not such a small amount of material is useful in a forensic context. There are several reasons to question whether or not it is. The 2013 review article by Meakin and Jamieson that I have previously cited is one source for information on low levels of DNA, and it mentions the problem that when an item of evidence is packaged the location of the DNA may be affected. Presumably this happens if the object tumbles around, coming into contact with the packaging and transferring the DNA to different locations on the object. The source of Amanda’s DNA on the blade may well be her DNA that was on the handle.

Dr. Schneps does not seem impressed with arguments based upon secondary or tertiary transfer. Nowhere in this passage does Dr. Schneps address the problem that Gubbiotti repackaged the knife. There was no reason whatsoever to do this, and I would have tossed the knife on the grounds that the packaged was opened alone, apart from all of its other problems. His clothing may have carried DNA from the flat to the station. I gave a citation some time ago in these threads which showed that DNA can be found on clothing that is neither from the wearer or his/her immediate family.

A major problem here may be that when DNA profiling was first introduced, large amounts of material were needed, a point that Dr. Gill made in a very recent interview. The introduction of PCR made it possible to test small samples, and the use of low template DNA requires even less material. As objects get smaller they are transferred more easily and in ways that are not always noticeable. Perhaps a simple analogy might help. An ordinary breeze is not strong enough to carry pebbles, but it is capable of blowing sand around.

I’d like to come back to the question of dedicated facilities because it is related to the question of aerosol DNA. Facilities working with low quantities of DNA often have special air handling needs, as I mentioned on my blog. If airborne contamination were impossible, as some PG-commenters seem to believe, then all the money that is spent on these facilities, and precautions such as pipet tips with aerosol barriers is wasted. BTW DNA may be detected several feet past where a person is speaking, which is further evidence of the existence of aerosol DNA. Dried blood is a more serious problem than wet blood from the point of view of aerosols.

An additional problem is what the SCC said about the test on 36I. They referred to it as “decisive.” How can it be decisive if the results are inculpatory, no matter which way the test turns out? A related problem is that Nencini turned aside valid requests from the defense, raising questions about his objectivity (and answering them).

Dr. Schneps does not address the paradox of DNA but no blood on the knife in this passage. The 2004 article by Peel and Gill makes me question more forcefully how this would even be possible. Nor does she address Stefanoni’s credibilitiy problems. In addition, the problem of laboratory contamination is far more extensive than the question of how many days elapsed since the last time a piece of equipment was used. For anyone to draw the inferences that Dr. Schneps does (that 36B is strengthened and that Vecchiotti was wrong) is completely unwarranted.

 

[MichaelB]

Here's an English translation of Sarah Gino Sept 26, 2009 if anyone is interested.

http://murderofmeredithkercher.com/wp-content/uploads/2014/11/Sarah-Gino-Testimony-English.pdf

 

[carbonjam72]

I haven't really been talking about luminol. I am taking aim at the supposed test that each scrap of evidence must pass through before it can be combined with other evidence to form part of the global evaluation.

I speak and write reasonably good English without having much acquaintance with the finer points of grammar. The law is the same. I don't have a bunch of governing principles to consult when I embark on evidence gathering (which is a large part of what I do for a living) and I view with deep suspicion the Italian claim to have formulated a coherent set of them. In the course of the discussion I have refined the Italian rule to my own satisfaction as follows: relevant evidence, even prima facie weak evidence, gets in unless it's total crap.

Using this rule, the luminol evidence in our case does not make it for all the reasons discussed here which, by an amazing coincidence (not), Nencini refrains from mentioning at all. In my system (and yours probably) he would not be allowed to find the luminol revealed blood because such a finding flies in the face of a concession Stefanoni made that if TMB is negative you can be sure it's not blood.

However, formulating a universal rule that luminol-only evidence should never be used regardless of context, is a bit like saying ID evidence should never be used merely because it is known to be often unreliable. That rule is too wide.

I think I can agree with pretty much everything here, with a possible exception to the highlighted.

Luminol isn't direct evidence in itself of anything other than a chemical reaction. It's a component is a series of tests, which once completed, create a finding that is evidence - whether false or positive for blood.

But luminol in itself is an incomplete test. In this way, using it as evidence seems premature. It seems like an incomplete investigatory stage, and rushing to present a half-truth, when a full result is still available.

So I think I like your view on evidence in general, but I think the luminol example is a weird exception.

My guess is, and perhaps I'm off on this, but we're used to thinking that because we use luminol as part of a test for blood, that a luminol reaction is evidence of, and can in itself be supportive of the possibility that blood is the substance causing the reaction. My problem is that our thinking of luminol as part of a 'blood test', doesn't make a luminol hit indicative that blood...

I'm lost. Maybe its like blood type evidence? A type B blood type could help narrow the field, and perhaps prevent an exclusion of a suspect, but not so far as to provide a certain confirmation of a suspect.

 

[anglolawyer]

I think I can agree with pretty much everything here, with a possible exception to the highlighted.

Luminol isn't direct evidence in itself of anything other than a chemical reaction. It's a component is a series of tests, which once completed, create a finding that is evidence - whether false or positive for blood.

But luminol in itself is an incomplete test. In this way, using it as evidence seems premature. It seems like an incomplete investigatory stage, and rushing to present a half-truth, when a full result is still available.

So I think I like your view on evidence in general, but I think the luminol example is a weird exception.

My guess is, and perhaps I'm off on this, but we're used to thinking that because we use luminol as part of a test for blood, that a luminol reaction is evidence of, and can in itself be supportive of the possibility that blood is the substance causing the reaction. My problem is that our thinking of luminol as part of a 'blood test', doesn't make a luminol hit indicative that blood...

I'm lost. Maybe its like blood type evidence? A type B blood type could help narrow the field, and perhaps prevent an exclusion of a suspect, but not so far as to provide a certain confirmation of a suspect.

As I have said more than once, luminol may not be the best exemplar of the point I'm making, precisely because it is capable of being rendered more or less certain by other tests. It is not fatal to my position if luminol is ruled everywhere around the world to be inadmissible if not confirmed as aforesaid. My target is Italian jurisprudence, not the science underlying testing for blood, as to which I have no relevant expertise.

 

[anglolawyer]

Sampson,

Thank you for posting that quotation. There are some problems in the reasoning employed, and it might be worth one’s while to examine them.

First is the question of what is meant by reliability or unreliability of a DNA profile in the context of forensics. It has been known for more than twenty years that one can use the polymerase chain reaction (PCR) to obtain DNA profiles from as little as one or two cells (I posted this information many continuation threads ago). Therefore, it is no surprise whatsoever that the Carabinieri were able to obtain a profile.

Second is the question of how the test was performed and reported. From what I recall, the Carabinieri created a consensus profile from two amplifications, whereas Stefanoni did just one. Someone else may know better than I do, but didn’t they also deposit electronic data files? In addition Stefanoni’s lab was not even certified for standard profiling at the time. I am not sure about the forensic lab of the Carabinieri, but for argument’s sake, let us say it was. A third problem is that low template work should be done in dedicated facilities, not in the same lab as the regular testing. These problems are all swept under the rug when one makes a hasty comparison between the results from two different labs.

IMO the most important question is whether or not such a small amount of material is useful in a forensic context. There are several reasons to question whether or not it is. The 2013 review article by Meakin and Jamieson that I have previously cited is one source for information on low levels of DNA, and it mentions the problem that when an item of evidence is packaged the location of the DNA may be affected. Presumably this happens if the object tumbles around, coming into contact with the packaging and transferring the DNA to different locations on the object. The source of Amanda’s DNA on the blade may well be her DNA that was on the handle.

Dr. Schneps does not seem impressed with arguments based upon secondary or tertiary transfer. Nowhere in this passage does Dr. Schneps address the problem that Gubbiotti repackaged the knife. There was no reason whatsoever to do this, and I would have tossed the knife on the grounds that the packaged was opened alone, apart from all of its other problems. His clothing may have carried DNA from the flat to the station. I gave a citation some time ago in these threads which showed that DNA can be found on clothing that is neither from the wearer or his/her immediate family.

A major problem here may be that when DNA profiling was first introduced, large amounts of material were needed, a point that Dr. Gill made in a very recent interview. The introduction of PCR made it possible to test small samples, and the use of low template DNA requires even less material. As objects get smaller they are transferred more easily and in ways that are not always noticeable. Perhaps a simple analogy might help. An ordinary breeze is not strong enough to carry pebbles, but it is capable of blowing sand around.

I’d like to come back to the question of dedicated facilities because it is related to the question of aerosol DNA. Facilities working with low quantities of DNA often have special air handling needs, as I mentioned on my blog. If airborne contamination were impossible, as some PG-commenters seem to believe, then all the money that is spent on these facilities, and precautions such as pipet tips with aerosol barriers is wasted. BTW DNA may be detected several feet past where a person is speaking, which is further evidence of the existence of aerosol DNA. Dried blood is a more serious problem than wet blood from the point of view of aerosols.

An additional problem is what the SCC said about the test on 36I. They referred to it as “decisive.” How can it be decisive if the results are inculpatory, no matter which way the test turns out? A related problem is that Nencini turned aside valid requests from the defense, raising questions about his objectivity (and answering them).

Dr. Schneps does not address the paradox of DNA but no blood on the knife in this passage. The 2004 article by Peel and Gill makes me question more forcefully how this would even be possible. Nor does she address Stefanoni’s credibilitiy problems. In addition, the problem of laboratory contamination is far more extensive than the question of how many days elapsed since the last time a piece of equipment was used. For anyone to draw the inferences that Dr. Schneps does (that 36B is strengthened and that Vecchiotti was wrong) is completely unwarranted.

Someone on another thread introduced me to the Dunning Kruger effect recently. IMO Ms Schaps, whom I regard as an honest but misguided poster on this case, greatly over reaches when she gets into the DNA evidence.

 

[Dan O.]

Au contraire! I am actually using LJ's recent blob on the carpet picture. I said nothing about the shape of a body, just the size, I think. But even I did, so what, the point remains the same: you can exclude all other likely sources of the reaction using TMB plus confirmatory testing or by other available circumstantial evidence such as I have described.

You did say a "body-sized shape" to which the natural bias would be to assume a body shape rather than a blob.

Is this the case where the investigators tried to develope latent fingerprints by heating superglue in the confined space and ended up torching the whole apartment? That would explain the lack of confirmatory testing.

Without confirmation you can't rule that the blob is blood. The size may be a clue as the the volume that was spilled. A box of wine that bursts open after falling off a ladder where the workers left it could perhaps create that size.

 

[anglolawyer]

Here's an English translation of Sarah Gino Sept 26, 2009 if anyone is interested.

http://murderofmeredithkercher.com/wp-content/uploads/2014/11/Sarah-Gino-Testimony-English.pdf

Looks great. I will read this avidly.

 

[anglolawyer]

You did say a "body-sized shape" to which the natural bias would be to assume a body shape rather than a blob.

Attendez, s'il vous plait! A body-sized shape is nothing at all like a body-shaped blob. So there.

Is this the case where the investigators tried to develope latent fingerprints by heating superglue in the confined space and ended up torching the whole apartment? That would explain the lack of confirmatory testing.

No, it's the case where a hurricane (or a big bad wolf) blew the house down and prevented further testing, or the samples were corrupted on the way back to or at the lab or some such mischance.

Without confirmation you can't rule that the blob is blood. The size may be a clue as the the volume that was spilled. A box of wine that bursts open after falling off a ladder where the workers left it could perhaps create that size.

Yes I can. Lets say there was no wine in the house and no evidence of any such thing ever being in the house. It can be a Mormon house (do they drink?).

 

[Desert Fox]

No, it's the case where a hurricane (or a big bad wolf) blew the house down and prevented further testing, or the samples were corrupted on the way back to or at the lab or some such mischance.

Being that cops are people, I would tend to believe that the samples were creatively lost or corrupted. Might be one of those exceptions to "Never attribute to malice that which is adequately explained by stupidity."

 

[anglolawyer]

Being that cops are people, I would tend to believe that the samples were creatively lost or corrupted. Might be one of those exceptions to "Never attribute to malice that which is adequately explained by stupidity."

Aaarrgghh!!! It doesn't matter DF! IT's only a freakin' thought experiment (obviously a very badly designed one).

 

[Numbers]

Turnip juice or blood. You decide.

Look, I can keep tweaking the thought experiment further if you want. You are already moving into the realm of fanciful explanation which lies beyond the zone of reasonable doubt and becomes too much to swallow. I mean, when was the last time you rolled in dirt and then came home and rolled around on the floor? Not impossible, just fanciful. And yes, I was posting in the context of a murder enquiry so it went without saying, I thought, that there had been a murder.

We agree the luminol evidence in this case is garbage. It doesn't even have zero value since the negative effect of the associated lies, certainly using Nencini's test (the one he sarcastically employed when rejected the defence request for re-testing of the clasp) obliges us to discount or discard all of Stefanoni's evidence. We don't agree whether luminol-only evidence can ever have probative value, even weak, non-zero value in the right context.[/QUOTE

The highlighted sentence above is not 100% true, assuming the "We" is meant to include me, "Numbers". But I am arguing for a very high bar before one can accept unconfirmed luminol CL as being probative. That is why I bring up the "rolling in dirt or mud". I believe many of us have (at least I have) rested on sand or on grassy soil without an intervening blanket. Now I didn't then lie down on a bare floor afterwards, but that would not be impossible in the real world. So I don't consider that scenario necessarily fanciful.

I've witnessed experimental surgery on sheep during which some of the sheep's blood squirted onto the op room floor. A tech then cleaned the blood from the floor (which was composed of some relatively smooth material without visible joints) with a damp sponge. There was no visible blood on the floor after the clean-up. If someone came and sprayed luminol on the floor after that clean-up, it would be likely that CL would be observed. Now I gave you the context, so you know there was no crime.

But suppose someone had been attacked and abducted at the University that day. The police come and try to find out what happened. They decide to luminol the floors. Something suspicious obviously happened in the animal surgery room - there's luminol CL and signs of a clean-up. A small group of men and women had been in that room earlier that day. What's the next step? Should the persons who had been in that room be arrested? Should there be some additional investigation, such as finding out whether the luminol CL is from human blood or some other substance, before the arrests are made?

Perhaps the above scenario may be a little less fanciful for you.

 

[Dan O.]

Yes I can. Lets say there was no wine in the house and no evidence of any such thing ever being in the house. It can be a Mormon house (do they drink?).

Perhaps not. But unless you are thinking of tha Amish, they likely didn't build the house themselves. Large quantities of spilled blood is still a very rare event so you need more than just Luminol to raise blood to the top causative agent. It's easy enough to see this by simply noting how hard you are trying to eliminate other causative agents.

If there were a background study to determine the prevalence of large luminol reactive stains in the common household, we could apply the math and give the probabilities given the known circumstances.